The San Francisco 49ers need a playmaker on the perimeter; veteran receiver Randy Moss can fill that role.

Football is a team sport, but every squad has a few players in the crosshairs each season; those guys who must step up for the team to flourish. On Tuesday, I identified two players from every AFC team (one on offense, one on defense) whose performances in 2012 will be absolutely key. Some are well-known, but many fly under the radar. Here is my list of crucial players from each NFC team:

ARIZONA CARDINALS

Offense: John Skelton, quarterbackSkelton has outstanding size (listed at 6-foot-6, 244 pounds) and good speed, and he can make all the throws. I think he'll likely start over Kevin Kolb. Skelton is one of the boys, so to speak, embraced by his teammates, who like the way he throws the ball. If the Cardinals are going to make the playoffs, Skelton has to pick up where he left off last season (6-2 record) and continue to get better.

Defense: William Gay, cornerbackGay isn't flashy, but he does make plays. Playing with the Pittsburgh Steelers last season, he allowed completions on just 39 of the 81 balls thrown his way (48.1 percent), according to STATS, LLC. He also allowed just one touchdown pass. He should help Patrick Peterson boost a defense that allowed 231 passing yards per game in 2011 (17th in the NFL).

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ATLANTA FALCONS

Offense: Sam Baker, offensive tackleBaker looked uninterested and almost passive in 2011, and wound up losing his starting job. He needs to regain the form that made him an integral part of the Falcons' 13-win team in 2010. New offensive line coach Pat Hill should really help him.

Defense: Akeem Dent, linebackerThe strong, explosive and mentally tough Dent will be asked to replace the departed Curtis Lofton. Dent has more upside than Lofton, and can potentially be better against the run, but can he play all three downs?

CAROLINA PANTHERS

Offense: Brandon LaFell, wide receiverLaFell doesn't have a ton of speed, but he is a big target (6-2, 210) and a great route-runner. If he continues to improve, he could become the big-play complement to Steve Smith that the Panthers have long needed. LaFell's blocking skills are key in Carolina, where they love to run the ball.

Defense: Luke Kuechly, linebackerAn improved defense (Carolina ranked 28th overall and gave up 429 total points) will get the Panthers to at least eight wins. Kuechly, the No. 9 overall draft pick in April, has great instincts, football I.Q. and character. He'll start on the weak side, but he can play all three spots, and I expect him to eventually move to the middle.

CHICAGO BEARS

Offense: J'Marcus Webb, offensive tackle Webb needs to come up big for quarterback Jay Cutler, who has been sacked 75 times over the past two seasons. The athletic Webb has tremendous upside and is still learning; he moved to left tackle in 2011 after spending his rookie year at right tackle. Offensive coordinator Mike Tice is an excellent offensive line coach who can get the best out of guys like Webb.

Defense: Stephen Paea, defensive tackleThe strong and fast Paea didn't start as a rookie last season, but he's probably the most improved Bears player in 2012. He's a good fit for Chicago's defense and should create more sack opportunities this season. Paea has been dealing with an ankle injury, but should be ready for the regular season.

DALLAS COWBOYS

Offense: Andre Holmes, wide receiverThe Cowboys need a third receiver. A small-school guy who was extremely productive at Hillsdale College, Holmes has the potential to be very good once he figures everything out. Holmes did undergo an MRI on his back this week, according to the Fort Worth Star-Telegram. If he misses time or falters, Cole Beasley, who is short (5-8) but was similarly productive at SMU, could step up.

Defense: Barry Church, safetyChurch doesn't seem to have very good speed at first glance, but he had an excellent time in the three-cone drill (6.65 seconds) at the 2010 NFL Scouting Combine, which shows he can change directions well. He has a feel for the game and plays with passion and physicality. He'll be an upgrade at safety for Dallas.

DETROIT LIONS

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Offense: Kevin Smith, running backYoung backs Jahvid Best and Mikel Leshoure are dealing with injuries, and the Lions need someone to carry their ground attack. It seems like Smith has been around forever, but he's only 25 and didn't play last year until Week 10, when the Lions brought him back after choosing not to re-sign him in the offseason. A strong inside runner who can catch balls out of the backfield and offers pass protection, Smith should start and be a big upgrade over what Detroit fielded for much of last season.

Defense: Jacob Lacey, cornerbackLacey wasn't great with the Colts in 2011, allowing 43 of the 65 balls thrown his way to go for completions (66.2 percent), according to STATS. But coach Jim Schwartz does a great job with defensive backs, and Lacey's quickness and competitiveness should make him a major upgrade over Aaron Berry, whom the Lions released after two offseason arrests.

GREEN BAY PACKERS

Offense: Marshall Newhouse, offensive tackleComing from a run-heavy college program at TCU, Newhouse didn't have much experience in pass protection and struggled as a fill-in starter for the Packers last season, giving up a ton of sacks. He has big hands and quick feet and seems to have gotten stronger and smarter, which are good signs.

Defense: Nick Perry, outside linebackerThe Packers must improve their pass rush. Forced to account for the strong, explosive Perry, offenses won't be able to double- or triple-team Clay Matthews as much as they did last season. Thus, Matthews should return to the form that saw him notch 13.5 sacks in 2010.

MINNESOTA VIKINGS

Offense: Toby Gerhart, running backGerhart was a capable fill-in for the injured Adrian Peterson last season, and finished with 721 yards from scrimmage and four touchdowns. No mere backup, Gerhart is a strong inside runner who can break arm tackles. He'll likely be used heavily early on, and when Peterson eventually gets back to full strength, the two backs can keep each other fresh.

Defense: Jasper Brinkley, linebackerThe talented and strong Brinkley didn't play a game in 2011 because of a hip injury. When you see him move around, he really looks good, but he hasn't exactly wowed in the preseason. The Vikings, however, didn't re-sign veteran E.J. Henderson, so they must feel Brinkley can do the job. (It's worth noting that a potential competitor for Brinkley, rookie Audie Cole, scored two touchdowns on consecutive interceptions within a 16-second period in a preseason victory over the Buffalo Bills.)

NEW ORLEANS SAINTS

Offense:Brian De La Puente, centerDe La Puente became a crucial part of the offense last season, but it took him a while to make that step. He spent time on the practice squads of four different teams over a period of three years before starting 12 games for New Orleans in 2011. The perseverance he showed in his fight for a job definitely carries over to the field. The smart, competitive De La Puente must continue to show he can play a key role.

Defense: Patrick Robinson, cornerbackRobinson has good coverage ability and led the Saints with four picks last season, but he'll have to be ready for offenses to pick on him in 2012. Jabari Greer was one of the best cornerbacks in the league in 2011, allowing just 48 of the 108 balls thrown his way to be caught (44.4 percent), according to STATS. Robinson will be tested.

NEW YORK GIANTS

Offense: Will Beatty, offensive tackleA talented up-and-comer who started 10 games last season, Beatty has the feet and speed to handle edge rushers. Beatty must get healthy. He's missed time with a back issue, but told the Daily News that he's gunning to be back on the field in time for the regular-season opener. The Giants need him to help protect Eli Manning.

Defense: Prince Amukamara, cornerbackAaron Ross is in Jacksonville and Terrell Thomas is still struggling with health issues, so Amukamara needs to step up and help strengthen a relatively weak pass defense. Amukamara is big (6-0, 210) and fast, but must get better at finding the ball.

PHILADELPHIA EAGLES

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Offense: Demetress Bell, offensive tackleThe Eagles signed Bell to help fill in for injured All-Pro tackle Jason Peters. Offensive line coach Howard Mudd should know how to push the right buttons with the athletic, long-armed Bell, getting him to play hard every down.

Defense: Kurt Coleman, safetyAfter allowing 27 touchdown throws in 2011, the Eagles need to tighten up their pass defense. Coleman is an instinctive player with excellent work habits who does very well against the run. He also had a team-high four picks and collected the squad's second-most tackles (78) last season. The Eagles need him to play even better in 2012; new secondary coach Todd Bowles will make that happen.

ST. LOUIS RAMS

Offense: Isaiah Pead, running backThe athletic, quick Pead can be the change-of-pace back the Rams need to complement straight-line runner Steven Jackson. St. Louis must score more in 2012. Pead, who is good on draw and screen plays, should help.

Defense: Cortland Finnegan, cornerbackFinnegan didn't play very well with the Titans in 2011, but he brings good coverage skills and competitiveness. Moreover, he's exactly coach Jeff Fisher's type. As a tough leader who's always barking at somebody, he can fill a crucial role by helping to mold the Rams' young defensive backs.

SAN FRANCISCO 49ERS

Offense: Randy Moss, wide receiverMoss can bring a lot to a San Francisco offense sorely lacked a playmaker in 2011. Jim Harbaugh is the right coach for Moss; he'll keep the receiver motivated and won't let him slack off. Moss, who still has great speed and receiving ability, seems to have landed in the perfect situation.

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Defense: Chris Culliver, defensive backThe 49ers had the NFL's best run defense in 2011, but ranked just 16th against the pass. The speedy Culliver has good hands and is very fluid. He should help as a third corner, though he can also play safety.

SEATTLE SEAHAWKS

Offense: Breno Giacomini, offensive tackleA former Packers prospect, Giacomini made a big leap in Week 11 of 2011, when he stepped into a starting role. The one-time college tight end has long arms and excellent work habits; his athletic ability and strength seem to have finally caught up with him. He's the kind of player offensive line coach Tom Cable loves to develop.

Defense: Bobby Wagner, linebackerThe competitive second-round draft pick must figure heavily into the Seahawks' plans; perhaps encouraged by Wagner's play, they traded free-agent acquisition Barrett Ruud to the Saints on Monday. The long-armed Wagner will make a lot of tackles, but he can also play in space.

TAMPA BAY BUCCANEERS

Offense: Dallas Clark, tight endThe Bucs spent a lot in free agency, but Clark might prove to be their most valuable addition. If he can stay healthy, the deceptively big 10-year veteran will create matchup problems for opponents. He is fast, can make clutch catches and will block. Clark should serve as an effective replacement for Kellen Winslow.

Defense: Gerald McCoy, defensive tackleA former top-three pick, McCoy has been hampered by injuries, but he must step up to help a unit that surrendered 494 points and ranked 30th in total defense (32nd against the run) in 2011. McCoy worked hard to get better over the offseason. New coach Greg Schiano is a defensive-minded guy who will recognize that McCoy is quicker than he is strong and maximize his talents.

WASHINGTON REDSKINS

Offense: Leonard Hankerson, wide receiverThe Redskins passed 191 times more than they ran in 2011; with Robert Griffin III under center, this trend will continue. With his big-play ability, I think Hankerson has a bit more upside than high-profile addition Josh Morgan. The speedy long-strider will really open some eyes if he has the kind of year I envision.

Defense: Josh Wilson, cornerbackThe Redskins gave up 22 passing touchdowns last season, but not for a lack of effort by Wilson, who allowed just 36 of the 85 balls thrown his way to be caught (42.4 percent), according to STATS. The sixth-year veteran had a career campaign in 2011; if he can repeat that kind of production in 2012, Washington's defense should be in good shape.